Pocket knife locking mechanism



Sept. 17, 1957 M. BERG 2,806,282

POCKET KNIFE LOCKING. MECHANISM Filed 001;. 14, 1954 Patented Sept. 17,1957 POCKET KNIFE LOCKING MECHANISM Martin Berg, New York, N. Y.

Application October 14, 1954, Serial No. 462,133

4 Claims. (Cl. 30-143) This invention relates to knife structures andmore particularly to a pocket knife structure provided with a lockingmechanism acting on the blades of the knife.

It is one of the main features of the invention to provide meansfacilitating the retention of the blades of a knife in retractedposition when the same is not in use.

It is another object of the invention to provide means enabling releaseof locking means for the knife blades upon displacement of a device orinstrument which is accommodated in a knife casing and which may becompletely removed from the latter for use.

It is a further object of the present invention to provide meansaffording the structure of a very compact combination knife and manicureinstrument, which is inexpensive to manufacture, as same comprises onlya few vital parts, and which is handy and sfie to carry around.

Yet another object of the invention resides in the provision of meansconducive to easy manipulation of the locking mechanism, whereby incompletely retracted position of said manicure instrument in the knifehousing the knife blade or blades are secured in inoperative position.

These and other objects of the invention will become further apparentfrom the following detailed description, reference being made to theaccompanying drawing, showing a preferred embodiment of the invention.

In the drawing:

Fig. 1 is a longitudinal section of a knife structure made in accordancewith the present invention and shown in closed and locked position;

Fig. 2 is a longitudinal section of the knife structure of Fig. l inopen position, the section being taken along line 2-2 of Fig. 3; and

Fig. 3 is a sectional view taken substantially along line 3--3 of Fig. 2with the bail pivoted to an upright position for ease of explanation.

Referring now more particularly to the drawing, there is shown anelongated casing or housing 10, substantially U-shaped in cross-section,and including side walls 11 and 12 each provided with a cut-out orindentation 13, a top wall 14 provided with an elongated slot oraperture 15, and an end wall 16 extending from the top wall 14 abouthalfway down side Walls 11 and 12.

A plurality of pivot axles 17, 18, 19 and 20 extend between the sidewalls 11 and 12. Within the housing 10, a rocker member 21 is pivotallymounted on axle 17, said rocker including a bifurcated tongue 22 and acatch 23 fixed at the end of the rocker opposite to the tongue. A bail24 is also pivotally mounted to swing about axle 1'7 and exteriorly ofthe housing.

A knife blade 25 is pivotally mounted adjacent the rounded end thereofabout the median portion of the axle 18. This rounded end of the knifeblade is provided with a shoulder 26 for a purpose hereinafterdescribed. On either side of the knife blade 25 a pair of lateral guides27, 28 are disposed, the axle 18 passing through said guides 27, 28.These guides are prevented from pivotal movement, however, since theyare elongated and also intersected by axle 19.

Axle 19 also passes through a blade spring 29, which includes aretaining portion 30, through which there passes axle 20. The bladespring further includes a resilient portion 31 on which there is mounteda leaf spring 32, which is in engagement with rocker member 21.

An implement 33 extends lengthwise of and into the housing and in closedor inoperative position occupies the space between top wall 14 and theupper ends of the lateral guides 27, 28 and of blade spring 29, theimplement including a tapered end or nose 34 and a pair of serrated legs35, underlying aperture 15. In the embodiment illustrated this implementcomprises a pair of mainicuring scissors.

As shown in Fig. 1, the tapered end 34 of the scissors seats in the baseof the bifurcated tongue 22 of the rocker member 21, thereby holdingsaid rocker in upwardly tilted position against the action of leafspring 32. In this position catch 23 of the rocker engages betweenshoulder 26 of the knife blade 25 and resilient portion 31 of the bladespring 29. As a result, the knife blade 25 cannot be pivoted about axle18 and is in a safe or locked position.

To open or unlock the knife blade 25 or like swingable instrument sothat the knife blade may be moved to the position shown in full lines inFig. 2, the operator engages the serrated portion 35 of the scissors 33through the aperture 15 and displaces the scissors to the right, asshown in dotted lines. As the end 34 is withdrawn from the bifurcatedtongue 22, the rocker is automatically pivoted about axle 17 under theaction of leaf spring 32 to the position shown in Fig. 2. In thisposition the catch 23 is withdrawn from the shoulder 26 of the knifeblade 25 and abuts against end wall 16 so that the knife blade may begrasped through indentations 13 and pivoted about axle 18 to openposition (from the closed position indicated in dotted lines). Theresiliency of portion 31 of the blade spring 29 serves to hold the knifeblade preferentially in either the open or closed positions. Inreclosing the structure the operation indicated is reversed.

The bail 24 may be employed for suspending the knife structure on a keyor watch chain, but may be omitted, if desired. Similarly, the implement33 need not be useful in itself as a pair of scissors but may beemployed solely for releasing the knife blade. It is preferable,however, that this locking mechanism serves a dual function. By makingthe catch portion 23 of the rocker 22 of resilient material, thescissors may be reinserted fully to its original position while thecatch portion is resiliently biased.

More than one knife blade or other tools may be mounted to swing aboutaxle 18 for locking in the manner indicated. If desired, other tools maybe mounted about axle 20 in a conventional manner, but they may not beprovided with a safety catch in accordance with the invention.

It can be seen that the knife structure herein provided is exceedinglycompact and may be manufactured easily and inexpensively. Nonetheless,provision is made for preventing the accidental opening of the knifeblade with its attendant hazards.

It can thus be seen, that there has been provided according to theinvention a knife or like tool structure having a casing and tool meanspivotally mounted for movement from a first position within said casingto a second position without said casing, said tool means being providedwith a shoulder, catch means cooperating with said shoulder of said toolmeans in said first position and mounted for movement to 'a secondlocation out of engagement with said shoulder, locking means releasablyholding said catch means in said first position, and spring meansnormally urging-said catch means into said second location, whereby uponrelease of said locking meansv movement of said catch means from saidfirst position to said second location is effected by said spring means,to

thereby permit pivotal; movement of; said tool; means to, said secondposition.

Variouschanges and modifications may be made without departing from thespirit and scope of the: present invention and it is intended that suchobviouschanges and modifications be embraced by the annexed'claims,

Having thus described the invention, what is claimed as new 'and desiredto be secured by Letters Patent, is:

1. A structure for a tool, such as a knife, comprising arr elongatedeasing substantially U-shaped in cross seetion and including abutmentmeans, tool means pivotally mounted for movementfrom a position within'said casing to a position without the'same, said tool means beingprovided with a shoulder, blade spring means within said casing andoverlying said shoulder of saidtool' means,- rocker. means pivotallymounted within said casing and including catch means, said rocker meansterminating in tongue means, locking means longitudinally displaceablewithin said casing and engageable with said tongue means of said rockermeans to thereby cause said catch means to engage between said bladespring means and said shoulder of said tool means, said tool means beingthereby locked against accidental pivotal movement, and leaf springmeans mounted on said blade spring means and urging said rocker meansagainst said abutment means in which position said catch means and saidshoulder become disengaged, whereby upon longitudinally displacing saidlocking means from engagement with said tongue means said leaf springmeans effects disengagement of said catch means from said shoulder tothereby free said tool means for pivotal movement.

2. In a structure according to claim 1, said locking means comprising ascissors, one end of said scissors being engageable with said tonguemeans.

3. A knife structure comprising an elongated casing having a pair ofside walls, a top wall connecting said side walls and an end wallextending between said side walls, a knife blade pivotally mountedbetween said side walls and provided with a shoulder, a rocker pivotallymounted between said side walls, said rocker being provided with abifurcated tongue at one end and with a catch at the opposite end,-saidoatch normally engaging with said shoulder of said knife blade, lockingmeans disposed for longitudinal movement within said casing, saidlocking means being provided with a nose engaging said bifurcated tongueof said rocker and maintaining said engagement of said catch with saidshoulder, and a spring disposed to urge said catch out of engagementwith said shoulder, whereby upon longitudinally displacing said lockingmeans within said casing said nose is disengaged from said tongue tothereby release said rocker, the latter being pivoted by said spring sothat said shoulder is freed from said catch which abuts against said"end wall, said knife blade being-thereby freed for pivotal movement.

4. In a knife structure according to claim 3, said top wall of saidcasing being provided with an elongated slot, said locking meanscomprising scissors including serrated legs normally disposed adjacentsaid slot, whereby said scissors may be displaced by manipulation ofsaid sernated legs through said aperture.

References Cited in the file of this patent France Dec. 23, 1953

